Harrow.



Patented Feb. 25, I902.

I J. B. monmsuu.

H ARROW.

(Application filed Feb. 21. 1901) 2 She ets Sheet 2.-

(No Model.)

. the connections.

UNITED STATES PATENT OFFICE.

JOSEPH B. MORRISON, OF FORT MADISON, IOWVA, ASSIGNOR TO MORRISONMANUFACTURING COMPANY, OF FORT MADISON, IOWA, A CORPORATION OF IOWVA.

HARROW.

SPECIFICATION forming part of Letters Patent No. 693,882, dated February25, 1902.

Application filed February 21,1901. Serial No. 48,228. No model.

To 0Z5 whom it may concern.-

Be it known that I, J osEPH B. MORRISON, of Fort Madison, Iowa, haveinvented certain new and useful Improvements in Harrows, ofwhich thefollowing is a specification.

This invention relates to that class of harrows in which thebarrow-teeth are fixed to tooth-bars which are mounted to rock in theframe, the several tooth-bars being connected and controlled by a singlelever, so that the teeth can be set and adjusted in any desired angularposition.

My invention consists, broadly stated, in the employment of a spring orelastic connection between the frame and the tooth-bars, in combinationwith a normally unlocked adju'sting-lever, whereby the barrow-teeth areheld normally in a set position determined by the setting of the stop ofthe operatinglever, but are permitted to yield to pass an obstructionencountered by any one of the teeth, all of which are restored to thenormal position by the spring when the obstruction is passed.

PreferablyI connect one end of the spring to one of the frame-bars bymeans of a lug or bracket and an eyebolt and the other end of the springto an arm on one of the'tooth-bars through the medium of a pivoted link,the connection being made in such manner that the link forms a lock whenthe teeth are thrown back to the full extent permitted by Thelocking-.lever I prefer to provide with a spring-actuated dog normallyheld out of engagement with the teeth of the ratchet-plate and to employa link on the ratchet-plate to furnish a back-stop to theoperating-lever.

In the accompanying drawings, Figure 1 is a plan view, partly brokenaway, of a harrowsection embodying my improvements. Fig. 2 is a sideelevation of the same, showing the parts in the working positionwith theteeth extended, so as to penetrate the ground. Fig. 3 is a sideelevation showing the tooth-bars rocked to carry the points of the teethbackward in position to clear them of trash and showing the spring fullyextended and points of connection in line, so that the spring is locked;and Fig. 4 is a sectional detail of the plunger-bolt or locking-dog andits keeper and showing the locking-pin therefor. In the drawings, 5represents the framebars, which are preferably metal beams of I-section.

6 represents the tooth-b'ars, which are of U form, as shown in Fig. 2,and to which are clamped the barrow-teeth 7. The tooth-bars are mountedso as to rock in the frame 'members, and the several bars haveupstanding arms 8, all of which are-pivotally connected by the link 9.Said link carries at its rear end the ratchet-plate 10.

11 represents the lifting-lever, which is pivoted to the frame and has alocking-dog or plunger-bolt 12, adapted to the teeth of theratchet-plate 10. This dog is normally depressed by the coil-spring 13and may be manipulated through the link 14 and latch 15. By means of thelever and its dog the teeth can be set at any desired inclination andthere locked it it be desired to provide a rigid construction. For thepurposes, however, of providing an elastic connection between thetooth-bars and the frame I prefer to hold the dog 12 out of engagementwith the ratchet, and this may be done, as shown in Fig. 4, by means ofthe cotter-pin 16. A loose link 17 or other equivalent back-stop devicemay be used, so as to hold the lever at any desired position forward ofits extreme backward limit of movement. .When the dog is held out ofengagement with the ratchet, the lever is of course free to play backand forth, and the, teeth may be adjusted to any position permitted bythe range of movement of the lever in front of its back-stop. .In orderto provide an elastic or yielding connection betweenthe tooth-bars andthe frame and to maintain the teeth in an operative position, while atthe same time permitting them to yield to obstructions, I employ theextensionspring 18, which is connected at its rear end to the eyebolt19,the latter passing through an aperture in an arm orbracket 20, boltedtothe frame-bar. The front end of the spring is connected to the bentlever 21, which in turn is pivoted to the crank 22, rigidly connected toone of the tooth-bars. Obviously the strength of the spring being dulyproportioned the teeth will be held in a working position, such as shownin Fig. 2, but are capable of yielding to pass an obstruction. Thespring being arranged to exert a constant pull, as soon as the teethhave passed such obstruction they will be automatically returned to theworking position. This construction affords two important resultsnamely,that it enables a more thorough cultivation of the ground, owing to theconstant vibratory action of the teeth, and, second, all jerking againstthe shoulders of the draftanimals is prevented, the elastic or yieldingconnection of the tooth-bars to the frame enabling the passing ofobstructions without noticeable jerk.

By throwing the lever to the extreme forward position, as shown in Fig.3, the teeth may be inclined at such an angle to the frame as to permitthem to be entirely cleared of trash or to pass an unusual obstruction.For this purpose it is desirable that the spring shall be prevented fromacting temporarily, and to this end I employ the bent lever or anequivalent construction, which will enable the point of connection withthe crank-arm on the tooth-bar to pass below or in line with a planedrawn through the axis of the toothbar and the fixed end of the spring.\Vhen so connected, the spring is temporarily neutralized, as shown inFig. 3, and the harrow may advance while it is being cleared of trash orbe transferred between fields without having the points of the teethpenetrating the ground.

hen it is desired to restore the harrow to working position, it is onlynecessary for the driver to exert suftieient force upon the lever 11 tocarry the end of the arm 22 slightly out of line, whereupon the tensionof the spring will immediately return the teeth to their normal positioneven against the resistance of the soil. This operation has heretoforebeen laborious, because the driver had not only through the hand-leverto overcome the friction of the several bearings, but also theresistance of the soil through which the teeth were being advanced.'VVith the construction above described the teeth may be thrown out ofaction and restored to the normal working position with the expenditureof slight force and during operation are constantly held by an elasticoryielding connection, thus rendering the implement more effective,while avoiding injury to the shoulders of the draft-animals and thedanger of breaking the teeth when encountering obstructions.

\Vhile I have described a particular construction and combination ofparts, it is obvious that my improvements are applicable to harrows ofdifferent structure and that some of the parts shown may be omitted. Forexample, I have shown an operating-1ever provided with a locking-dogadapted to work in conjunction with a ratchet-plate. This is the usualconstruction butit provides a rigid harroW-that is, one which is withoutyield during operation. I have shown my improvements applied to such aharrow, because it may be found desirable to combine such improvementswith a harrow of such usual construction; but it will be understood thatthe lifting-leveris not an essential feature of the combination and thatthe liftinglever, link, and ratchet-plate form for the broader purposesof my invention a single elementi. 8., a baek-stop-and that suchback-stop might be provided in other ways were the lifting-lever andratchet-plate omit-- ted, since the driver will usually throw the pointsof the teeth back and clear the l1arrow of trash by placing his foot onthe upper end of one of the teeth or on the frame, while to break thelook a slight pull on the frame with the points of the teeth heldagainst backward movement will bring the spring into action and restorethe harrow to working position. I prefer to use the lifting-lever, withits locking-dog and the ratchet-plate, for convenience in handling theharrow and also to adapt it to be used in the old Way when desired; butinstead of the locking-pin 16 any other convenient locking device tohold the dog out of action may be employed, such as the ring-latch 22.(Shown in Fig. 2.) The frame of the harrow may be made from gas-pipe orangle-bars. or of any other suitable construction, and other of thestructural details may be varied within the scope of this invention.

I claim-- 1. In a harrow of the class described, the combination withthe frame, of a series of connected tooth-bars mounted to rock therein,a crank secured with one of said toothbars and a spring connected at oneend to the barrow-frame and at the other to the crank, said point ofconnection being adapted to be moved into line with the axis of thetoothbar and thepoint of connection of the spring to the frame,substantially as described.

2. In a harrow of the class described, the combination with a rigid mainframe, of a series of parallel tooth-bars mounted to rock therein, eachof said bars being provided with an upstanding crank-arm projection, alink pivotally connected with the several cranks of the tooth-barswhereby they are connected to move in unison, a notched segment carriedby said link, a locking-lever rigidly connected with one of the rockingtoothbars and arranged to cooperate with said segment, and a coiledcontractile spring con- IIO pivotally connected with the several cranksof the tooth-bars whereby they are connected relative arrangement of thespring, bent link to move in unison, a notched segment car and crank-armbeing-such'that the spring ried by saidlink, a locking-lever rigidlyconmay be movedinto position to exert its tennectedcwith one of therocking tooth-bars and sion to either hold the teeth in or out of op- 5arranged to cooperate with said segment, a erative position,substantially as described. 15

coiled contractile spring connected at one end with the rigid frame, andat its opposite JOSEPH MORRISON end with a bent link, and a crank-armupon Witnesses: one of said rocking tooth-bars with which EDGAR \V.CAMP,

10 said bent link is operatively connected, the V. E. MORRISON.

